PSAIX (black) is PIMCO world bond fund based on their proprietary “GLADI” index, a GDP weighted index of investment grade bonds worldwide (see some details from the GLADI profile below).
World bonds = black
US Treasuries = gold
DM (developed markets) sovereigns = red
EM (emerging markets) sovereigns = blue
GLADI Regional Weights:
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Difference Between Market-Cap Weighting and GDP Weighting: